Selective call receivers, e.g. pagers, typically alert a user upon the occurrence of one of a number of possible events. The alert can be an audible or a tactile alert. The latter alert provides a silent alert signal to the user.
The current art requires two separate devices within the selective call receiver to perform the two alerts. Referring to FIG. 1, conventional designs require a vibrator motor 100 comprising a cylindrical housing 102 having a rotating shaft 104 attached to an external unbalanced counterweight 106 to provide the "silent" tactile alert. The cylindrical body 102 is held in place on a printed circuit board 108 by motor bracket 110. Additionally, a separate transducer (or amplifier and speaker system) is required to provide the audible alert.
The required two devices add substantial size and cost to the receiver. Also, they increase the amount of time required to assemble and to service the product. Ultimately, the reliability of receivers is degraded by the inclusion of these two electro-mechanical devices.
Conventional message alert designs also impede miniaturization, which is a significant drawback to modern receiver design trends. It is important that the overall size be reduced without reducing the vibration level required for the "silent" tactile alert, since this would defeat the advantage of the size reduction.
Accordingly, there exists a need in the art for a single, high reliability device to provide both the audible and tactile alerts.